Tony,
I guaranty that the key isn't going to be a "VLK" volume license key. What it will be is a OEM SLP key. This key will provide SLP activation on HP computers with a BIOS that has a v2.1 SLP/SLIC table. This key requires the use of a matching OEM SLP certificate. All of your Pro 3500's will have the same key/cert. combo.
1) Download and unzip ABR Beta With Windows 7 Support. Here is the main page to ABR for Windows Vista. Please follow the "How to use it" section for information and instructions on how to use it. These steps apply to Windows 7 as well. Perform the "activation backup" on each computer and save the recovered key and certificate in seperate locations for comparision.(This pulls the original factory HP OEM preinstalled key and OEM certificate from your factory installed OS) Compare the keys and certificates from a couple of computers, are they all the same??? Please report back with your findings.
2) Download and use RWEverything to determine the OA/SLP/SLIC version in the computer's BIOS. Refer to this MyDitigalLife webpage entitled "How to Check or Verify PC Motherboard BIOS SLIC Version is SLP OA 2.0 or 2.1 for OEM Activation" for information on how to use and decipher the information. (Windows 8 use OA 3.0 and this is where the problem may occur)Please report back with your findings.
3) Install Windows 7, following all prompts as needed. Don't allow Windows to try to auto-activate. Run ABR "activation restore" to "install" the previously backed up product key and certificate. Verify that Windows is activated, repeat "activation restore" until Windows 7 is activated. (This "installs" the original factory HP OEM pre-installed key and certificate from your factory installed OS to your clean Windows install. This HP OEM key and HP OEM certificate, along with the BIOS is what allows your HP computer to be factory pre-activated.)
4) Install all needed drivers for the computer. These can be found on HP support page for your computer or you can find newer drivers on the various component manufacturers websites... Intel, NVidia, AMD/ATI, Ralink, Realtek, etc.
5) Install all company required software and updates.
6) Image the Windows installation and deploy on the remaining computers.
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